`whereIn` with non-sequential keys produces an invalid `terms` filter (terms_lookup error)

[tobiasnitsche]

Version

• directorytree/opensearch-scout-driver: v1.1.0

Description

SearchRequestPayload::makeFilter() builds each terms filter directly from
$builder->whereIns values without reindexing them:

foreach ($builder->whereIns as $field => $values) {
    $filter[] = ['terms' => [$field => $values]];
}

When a values array has non-sequential integer keys, json_encode() serializes it as a
JSON object instead of an array. OpenSearch then reads the object form under terms
as a terms lookup and rejects the request.

This happens with ordinary input — e.g. a values array left keyed by array_unique()
(which preserves keys) or a keyed pluck().

To reproduce

$values = array_unique(['active', 'active', 'invited']); // [0 => 'active', 2 => 'invited']

Model::search('foo')->whereIn('status', $values)->get();

The generated filter becomes:

{ "terms": { "status": { "0": "active", "2": "invited" } } }

Expected

{ "terms": { "status": ["active", "invited"] } }

Actual

OpenSearch returns HTTP 400:

x_content_parse_exception: [1:2039] [terms_lookup] unknown field [1]

Suggested fix

Reindex the values in makeFilter() so a terms filter always serializes as a JSON
array (whereIn means "field is one of this list", so the value is never meant to be an
object / terms lookup):

$filter[] = ['terms' => [$field => array_values($values)]];